linux-stable/fs/dlm/netlink.c
Johannes Berg ef6243acb4 genetlink: optionally validate strictly/dumps
Add options to strictly validate messages and dump messages,
sometimes perhaps validating dump messages non-strictly may
be required, so add an option for that as well.

Since none of this can really be applied to existing commands,
set the options everwhere using the following spatch:

    @@
    identifier ops;
    expression X;
    @@
    struct genl_ops ops[] = {
    ...,
     {
            .cmd = X,
    +       .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
            ...
     },
    ...
    };

For new commands one should just not copy the .validate 'opt-out'
flags and thus get strict validation.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-27 17:07:22 -04:00

141 lines
3 KiB
C

/*
* Copyright (C) 2007 Red Hat, Inc. All rights reserved.
*
* This copyrighted material is made available to anyone wishing to use,
* modify, copy, or redistribute it subject to the terms and conditions
* of the GNU General Public License v.2.
*/
#include <net/genetlink.h>
#include <linux/dlm.h>
#include <linux/dlm_netlink.h>
#include <linux/gfp.h>
#include "dlm_internal.h"
static uint32_t dlm_nl_seqnum;
static uint32_t listener_nlportid;
static struct genl_family family;
static int prepare_data(u8 cmd, struct sk_buff **skbp, size_t size)
{
struct sk_buff *skb;
void *data;
skb = genlmsg_new(size, GFP_NOFS);
if (!skb)
return -ENOMEM;
/* add the message headers */
data = genlmsg_put(skb, 0, dlm_nl_seqnum++, &family, 0, cmd);
if (!data) {
nlmsg_free(skb);
return -EINVAL;
}
*skbp = skb;
return 0;
}
static struct dlm_lock_data *mk_data(struct sk_buff *skb)
{
struct nlattr *ret;
ret = nla_reserve(skb, DLM_TYPE_LOCK, sizeof(struct dlm_lock_data));
if (!ret)
return NULL;
return nla_data(ret);
}
static int send_data(struct sk_buff *skb)
{
struct genlmsghdr *genlhdr = nlmsg_data((struct nlmsghdr *)skb->data);
void *data = genlmsg_data(genlhdr);
genlmsg_end(skb, data);
return genlmsg_unicast(&init_net, skb, listener_nlportid);
}
static int user_cmd(struct sk_buff *skb, struct genl_info *info)
{
listener_nlportid = info->snd_portid;
printk("user_cmd nlpid %u\n", listener_nlportid);
return 0;
}
static const struct genl_ops dlm_nl_ops[] = {
{
.cmd = DLM_CMD_HELLO,
.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
.doit = user_cmd,
},
};
static struct genl_family family __ro_after_init = {
.name = DLM_GENL_NAME,
.version = DLM_GENL_VERSION,
.ops = dlm_nl_ops,
.n_ops = ARRAY_SIZE(dlm_nl_ops),
.module = THIS_MODULE,
};
int __init dlm_netlink_init(void)
{
return genl_register_family(&family);
}
void dlm_netlink_exit(void)
{
genl_unregister_family(&family);
}
static void fill_data(struct dlm_lock_data *data, struct dlm_lkb *lkb)
{
struct dlm_rsb *r = lkb->lkb_resource;
memset(data, 0, sizeof(struct dlm_lock_data));
data->version = DLM_LOCK_DATA_VERSION;
data->nodeid = lkb->lkb_nodeid;
data->ownpid = lkb->lkb_ownpid;
data->id = lkb->lkb_id;
data->remid = lkb->lkb_remid;
data->status = lkb->lkb_status;
data->grmode = lkb->lkb_grmode;
data->rqmode = lkb->lkb_rqmode;
if (lkb->lkb_ua)
data->xid = lkb->lkb_ua->xid;
if (r) {
data->lockspace_id = r->res_ls->ls_global_id;
data->resource_namelen = r->res_length;
memcpy(data->resource_name, r->res_name, r->res_length);
}
}
void dlm_timeout_warn(struct dlm_lkb *lkb)
{
struct sk_buff *uninitialized_var(send_skb);
struct dlm_lock_data *data;
size_t size;
int rv;
size = nla_total_size(sizeof(struct dlm_lock_data)) +
nla_total_size(0); /* why this? */
rv = prepare_data(DLM_CMD_TIMEOUT, &send_skb, size);
if (rv < 0)
return;
data = mk_data(send_skb);
if (!data) {
nlmsg_free(send_skb);
return;
}
fill_data(data, lkb);
send_data(send_skb);
}